A power supply regulator, such as an LDO (Low Drop Out) regulator, and a power supply switch, such as a load switch, are each used as a power supply circuit for supplying electric power to a load, such as an electrical instrument. Each of these power supply circuits includes a discharge circuit for discharging the load (i.e., removing electric charge accumulated in the load) when the supply of the power to the load is stopped. When switching into a discharging state, a conventional discharge circuit will maintain the discharging state even after the load discharging has been completed. Because of this, an unintended high current (also referred to as “short-circuit current”) flows between the load and a ground via the discharge circuit, and this flow often causes the load to breakdown.